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    Re: Still on LOP's (mea culpa)
    From: Michael Wescott
    Date: 2002 Apr 26, 10:26 -0400

    >> Given that each observation comes from the same Gaussian distribution
    >> the joint probability density is proportional to
    >>
    >>        exp( -(d1**2 + d2**2 + d3**2 ... ))
    >>
    >> where dn is the distance from a point to LOP number n. So it's
    >> a matter of minimizing d1**2 + d2**2 + d3**2 ...  to get maximum
    >> joint prob density or MPP. In other words it's a least squares problem.
    
    > Now I am getting confused anew. If the sigma is the same for each LOP,
    > then how can the expression below weight dN differently from dM. All
    > the d's are squared inside the exp(). So in a 3-LOP case, how could the
    > center be anything but the center of the inscribed circle (i.e. all d
    > the same value)?
    
    By geometry. If you move the candidate point for MPP almost parallel to
    side N and side P, dM can get smaller faster than dN and dP get bigger.
    It depends on their mutual orientation.
    
    
    
    --
            Mike Wescott
            Wescott_Mike@EMC.COM
    
    
    

       
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